Conventional LED display systems include arrays of light units, with each light unit including one or more LED's. It is conventional to interface such LED display systems to a computer so that the computer may supply control signals to selectively activate individual ones of the light units.
However, the efficiency and lifetime of the individual LED's employed in such systems has been limited due to the high junction temperature of each LED, resulting from the large amount of heat generated in each LED while it emits light. Additionally, the use of square wave control signals to switch each LED between an "on" and an "off" mode has resulted in radiation of a substantial amount of radio frequency interference. Further, the interface between the computer controller and the light units in such conventional systems has typically had complicated design.
It has not been known until the present invention how to construct an LED display system so as to avoid all of these problems.